Hair is a keratinous substance, which is constantly subjected to environmental stresses such as low humidity, UV radiation, contact with surfactants, and physical abrasion, and also to internal stresses which are a consequence of the natural aging process. Because of these stresses, hair looses its natural conditioning and moisturizing components and often appears rough, dry, and damaged. Thoroughly cleansed hair is extremely difficult to comb, in either the wet or the dry state, because the individual hair fibers tend to snarl, kink and interlock with each other. In addition, incompletely dried hair, such as hair dried with towel, has poor brushing properties, and after complete drying, the hair does not set well. Furthermore, the combing or brushing property of the hair remains poor, and the hair has undesirable electrostatic properties in a low humidity atmosphere that causes the hair to xe2x80x9cfly awayxe2x80x9d, thereby further reducing the brushing properties of the hair. The unsatisfactory combing or brushing property of hair immediately after shampooing also causes hair damage, such as split ends or hair breakage.
xe2x80x9cSplit endsxe2x80x9d refers to a condition wherein the ends of the hair are split into two or more shafts, resulting in a frizzy appearance. Numerous conditioner and shampoo formulations have been developed in an effort to ameliorate split ends. The majority of these seek to prevent split end damage as opposed to repairing split ends. Known compositions that do seek to repair split ends include those disclosed in U.S. Pat. No. 6,258,348 B1 (xe2x80x9c""348 Patentxe2x80x9d), the complete disclosure of which is hereby incorporated by reference. The compositions disclosed in the ""348 Patent as being useful in split-end repair comprise three polymers: guar, a betaine-based polyurethane surfactant, and a silicone polyurethane. In particular, the ""348 Patent discloses that formulations comprising amphoteric or cationic guar (e.g., guar hydroxypropyl trimonium chloride, CTFA nomenclature), in combination with polymeric adhesive agents comprising a betaine based polyurethane surfactant and a silicone polyurethane, can repair a substantial percentage of various split end test samples. According to the disclosure of the ""348 Patent, the amphoteric or cationic guar gums do not achieve substantial split end repair in the absence of the other disclosed polymeric substituents.
U.S. Pat. No.4,548,810 (xe2x80x9c""810 Patentxe2x80x9d), the complete disclosure of which is hereby incorporated by reference, discloses fatty dimethyl amine salts, which are known generally by the trade name xe2x80x9cNeconxe2x80x9d (Necon(trademark)) and which are available commercially from Alzo International, Inc., Sayreville, N.J. In particular, the Necons are long chain tertiary amine salts of fatty acids ranging from C6 through C36 and have been used in skin and hair contacting formulations in such applications as shaving creams, skin creams, lotions, bar soaps, liquid soaps, body oils, hair colorants, afterbath lotions and splashes, lipsticks, lip balms, bath products and sunscreen formulations for their attributes of assisting in the solubilization of components in these formulations and their conditioning characteristics of the skin and hair.
As disclosed in the ""810 Patent, the Necons are non-adhesive compositions which increase the slip and lubricity of hair, and as such they would not be expected to contribute to split end repair if included in a hair conditioning formulation. This is because, unlike the polyurethane surfactant and silicone polyurethane components described in the ""348 Patent, the Necons would not be expected to deposit on a hair surface in a manner thought necessary to repair split ends. As is the case with other agents traditionally used to increase the slip and lubricity of hair such as stearalkonium chloride, the presence of a Necon alone in a hair conditioning formulation does not appear to contribute to the repair of split ends.
There has been no suggestion that a Necon could be substituted in guar gum-containing hair conditioning formulations for other non-guar polymeric constituents, such as the betaine-based polyurethane surfactant or silicone polyurethane described in the ""348 Patent, to make a formulation which achieves substantial split end repair.
The present invention provides a hair conditioning formulation useful in repairing split ends comprising: (a) an amphoteric or cationic guar gum, preferably a cationic guar gum, even more preferably a quaternary ammonium derivative hydroxypropylguar; and (b) a fatty dialkyl (preferably, dimethyl) amine salt (Necon) as otherwise described herein, wherein the formulation may contain a natural or synthetic gum.
In a preferred embodiment, the formulation of the instant invention is a shampoo comprised of an amphoteric or cationic guar gum and one or more fatty dimethylamine salts selected from the group consisting of:
polyethyleneoxide 15-cocamine phosphate/oleate complex (Necon(trademark) CPS-65),
lauryldimethylamine lactate (Necon(trademark) LL),
lauryldimethylamine oleate (Necon(trademark) LO),
lauryldimethylamine dimer dilinoleate (Necon(trademark) DLD),
linoleamidopropyldimethylamine lactate (Necon(trademark) SOLC), behenamidopropyldimethylamine behenate (Necon(trademark) BAB), behenamidopropyldimethylamine dimer dilinoleate (Necon(trademark) BD), and linoleamidopropyldimethylamine dimer dilinoleate (Necon(trademark) LO-80). All of the above Necon products are available commercially from Alzo International, Inc., Sayreville, N.J.